Foaming refers to a process of producing a cellular structure in a variety of materials such as plastics, rubbers, etc. by using a blowing agent whereby gas is produced under specific temperature, pressure and time conditions, thus giving foams.
Disposable containers may be classified into non-foam type and foam type etc. A non-foam type disposable container may be manufactured relatively easily by vacuum molding, pressure forming, etc. However, the non-foam type disposable container is problematic in that, when hot materials are put in the container, the heat may be transferred to outside without blocking and thus may cause burning of human skins which the container may be in contact with.
A foam disposable container may be manufactured from non-degradable plastic materials such as PS, PP, PE, etc. via a foaming process. Although the container may be lightweight, have good cushioning and insulating properties, and allow cost reduction, the disposable container which is made from synthetic resins or plastics may cause environmental pollution.